Skiving machine



H. E. ARMSTRONG SKIVING MACHINE May 13, 1941.

Filed May 29, 1940 Patented May 13, 1941 SKIVING MACHINE Howard E. Armstrong, Johnson City, N. Y., assignor to United Shoe Machinery Corporation, Borough of Flemington, N. J., a corporation of New Jersey Application May 29, 1940, Serial No. 337,858

4 Claims.

This invention relates to skiving machines and is herein illustrated as embodied in a machine for skiving the margins of pieces of upper leather, such as are used, for example, in the manufacture of boots and shoes.

Machines of this kind commonly comprise a feed roll against which the work is held by a presser as it is advanced to a skiving knife, the presser being urged toward the roll by yielding means such as a spring, It sometimes happens that the leather pieces which are to be skived, or some of them, are pieces which are hard and bony in spots; and when such spots are encountered they are liable not to be held down properly upon the roll, with the result that the knife cuts a gouge in the work. In order to avoid such undesirable results, as well as to provide for any case in which a pressure greater than usual should be applied, a second yielding means is provided for urging the presser toward the feed r011. This second means, which is supplemental to the first-named means, is normally inoperative but becomes operative when the presser is moved more than a given distance away from the feed roll.

This and other features of the invention, including certain details of construction and combination of parts, will be described as embodied in an illustrated machine and pointed out in the appended claims.

Referring to the accompanying drawing,

Fig. 1 is a view in front elevation of a skiving machine in which the present invention is embodied; and

Fig. 2 is a view, partly in elevation and partly in section, showing more particularly the construction of the presser and the two yielding means for urging it toward the feed roll.

The illustrated machine, except for the supplementary yielding means for acting upon the presser, is or may be substantially the same as the machine disclosed in United States Letters Patent No. 1,866,918, granted July 12, 1932, on an application filed in the name of Milton H. Ballard. The machine comprises a rotary feed roll I I and a rotary feed disk It, which co-operate to feed the Work away from the observer to a rotary disk knife I5, the edge of the work contacting with an edge guide i1, and the margin of the work being pressed down upon the feed roll ll by a presser 19. The knife H3 is adjustable up and down but is held from angular movement. In order to vary the angle of the scarf, the feed roll, the feed disk, the edge guide and the presser are all mounted directly or indirectly upon a carrier, a portion of which is shown at 21, said carrier being angularly adjustable in a path perpendicular to the direction of feed movement of the Work. The presser 19 has an upwardly extending stem 23, which is vertically slidable in a bore formed in a boss I25 at the outer end of an arm 25, the inner end of said arm being slidably mounted for substantially horizontal adjustment on the lower portion of a bracket 21, which is adjustably fastened to the carrier 2|, the arm 25 being held in adjusted position by a screw 29, which passes through a slot in the bracket and is threaded into the arm. In order to exert a downward pressure upon the presser, one end of a bent lever 3| extends through a slot in the wall of the boss I25 and into a slot in the stem 23, said lever being urged at all times to rotate in a counterclockwise direction about its pivot 33 by a compression spring 35, one end of which is seated in a socket in the arm 25 and the other end of which abuts against the end of a small screw 31, which is threaded through the lever 3!. The presser is thus continually urged downward, the extent of such downward movement being limited by a stop nut 39 threaded on the stem 23. The machine, as thus far described, except for the shape of the arm 25, is or may be the same as that of the patent to which reference is made for details not herein set forth.

The arm 25 has extending through it, below and parallel to the stem of the adjusting screw 31, a bore having portions of three different diameters. The stem of a small plunger 4| extends through the portion of smallest diameter. A compression spring 43, located in the portion of medium diameter, engages with one end the head of the plunger and with the other end one end of an adjusting screw 45, which is threaded into the portion of largest diameter and is held in adjusted position by a pinch screw 56. Threaded through the upwardly extending arm of the lever 3| substantially in line with the plunger ti is an adjusting screw 41, which is held from accidental turning by a coil spring 49. With the parts in the positions shown, the effect of putting a piece ofleather through the machine is to raise the presser 69 against the force of the spring 35. Whether or not the spring 43 will come into play will depend upon the nature of the leather and the position of the adjusting screw ll. By adjusting this screw, the point in the upward movementof the presser, at which the supplemental spring 43 becomes efiective, may be predetermined. Thus, for example, if pieces of leather having hard bony spots are to be skived, the screw 41 may be adjusted into a position such that, when these hard spots are encountered and tend to move the presser up, the supplemental pressure means becomes effective. In general, the position to which the screw 41 is adjusted determines at what point in the movement of the presser away from the feed roll the supplemental yielding means becomes effective. Obviously, if the screw 41 is adjusted into a position in which it contacts with the plunger 4! when there is no work in the machine, both of the yielding means will act upon the presser at all times.

urge the presser toward the roll, a supplemental normally inoperative yielding means, and an adjustable member for rendering the supplemental yielding means operative when Work passing between the presser and the roll exceeds a given thickness.

3. A skiving machine having in combination a knife, a feed roll for advancing the work to the knife, 2, presser for holding the work against the feed roll, a lever engaging the presser foot, a spring acting at all times upon the lever to urge the presser toward the food roll, a supplemental Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A skiving machine having in combination a knife, a feed roll for advancing the work to the knife, a presser for holding the work against the roll, yielding means acting at all times to urge the presser toward the roll, a supplemental yielding means, and adjusting mean for predetermining the point in the movement of the presser away from the roll at which the supplemental yielding means becomes effective.

2. A skiving machine having in combination a knife, a feed roll for advancing the work to the knife, a presser for holding the work against the roll, yielding means acting at all times to spring, and an adjustable member the position of which determines at what point in the travel of the lever said supplemental spring become effective 4. A skiving machine having in combination a rotary disk knife, a feed roll for advancing the work to the knife, a presser for holding the work against the roll said presser being mounted for sliding movement toward and from the roll, a stop for limiting the extent of movement toward the roll, a lever for urging the presser toward the roll, yielding means acting at all times upon the lever, and a normally inoperative supplemental yielding means adapted to become operative when the presser is moved more than a given distance away from the roll.

HOWARD E. ARMSTRONG. 

